Mechanism of the interaction of color reagent 1, 3-N, N'-bis-4-(4'-nitro benzenediazo) phenyl squaraine with oxoacid anions

By AM1 method, the interactions between 1, 3-N, N′-Bis-4-(4′-nitro benzenediazo) phenyl squaraine (BNBPS) and several oxoacid anions have been studied on the basis of the proposed model. The mechanism of the color reactions is suggested and the answers to the question of whether or not BNBPS colorates with HCO_3~-, CO_3~(2-), NO_2~(-), NO_3~-, etc. are given. It is theoretically predicted that BNBPS might be used as the color reagent for SO_4~(2-).     

Cayley color graphs of inverse semigroups and groupoids

The notion of Cayley color graphs of groups is generalized to inverse semigroups and groupoids. The set of partial automorphisms of the Cayley color graph of an inverse semigroup or a groupoid is isomorphic to the original inverse semigroup or groupoid. The groupoid of color permuting partial automorphisms of the Cayley color graph of a transitive groupoid is isomorphic to the original groupoid.     

Control of the Rendition Wavelength Shifts of Color Lippmann Holograms Recordedin Single-layer panchromatic Silver-halide Emulsion

1 Introductionther hologratns can be used for artWork fabrication, product advertisement,museum item presentation, etc., and have wide applicationS in the world of businessand everyday life. To be able to record high-quality color reflection holograrns, it isnecessary to use extremely low scattering recording materials, for example, the use ofultra-high resolution silver-halide emulsions. Russian PFG-03C panchromatic silverhallde Plate is such a recording material, which has some excellent c…     

Irreversible helix rearrangement from Cis‐transoid to Cis‐cisoid in poly(p‐n‐hexyloxyphenylacetylene) induced by heat‐treatment in solid phase

Polymerization of p‐n‐hexyloxyphenylacetylene (pHPA) by using a [Rh(norbornadine)Cl]₂‐triethylamine catalyst was carried out at room temperature to afford stereoregular helical poly(p‐n‐hexyloxyphenylacetylene)s (PpHPAs). When ethanol and n‐hexane were used as polymerization solvents, a bright yellow PpHPAs, poly( Y ) with M_n = 8.5 × 10⁴ and its purple red polymer, poly( R ) with M_n = 5.3 × 10⁴ were obtained in 95% yields and 84% yields, respectively. Diffuse reflective UV–vis spectra of poly( Y ) and poly( R ) in solid phase showed different broad absorption peaks at 445 and 575 nm, respectively. X‐Ray diffraction patterns of poly( Y ) and poly( R ) showed typical columnar structures assignable to cis‐transoid and cis‐cisoid structures, respectively, which were also supported by molecule mechanics calculation. Poly( Y ) was irreversibly transformed to a reddish‐black polymer, poly( Y‐B ), which columnar diameter was nearly the same as that of poly( R ). Further, poly( Y ) showed an exothermic peak in the differential scanning calorimetry trace at 80 °C for 1 h in N₂ gas. Thus, these findings suggest a thermally irreversible rearrangement from an unstable cis‐transoid form, poly( Y ) with a stretched cis‐transoid helix to a stable cis‐cisoid form, poly( R ), with a contracted cis‐cisoid helix in the solid phase to give poly( Y → B ) with the cis‐cisoid form. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

Color appearance seen through a colored filter of various sizes

It will provide us an effective method to study the color perception of the elderly if we can employ for young subjects a pair of glasses with color property chosen to simulate that of the elderly. One problem has to be solved before using such glasses based on the concept of the recognized visual space of illumination, that is, the size of the glasses. When a piece of a white paper is seen through a yellow filter in a room, it naturally appears yellowish. But if the observer uses the filter to cover his/her eyes entirely the white paper returns to its original white; this is known as color constancy. Between these two extreme cases, the color is expected to change from yellow to white. Chromaticness and hue of an achromatic test chart of a small or large size were determined by the elementary color naming method when the chart was seen monocularly through a red, yellow, green or blue filter, respectively, placed at various distances from the eyes. Chromaticness was large at around 40% when the visual field through the filter was equal to or smaller than the test chart, but it rapidly decreased when the visual field extended over the test chart so that objects other than the test chart were included in the visual field. It decreased to almost zero when the filter was about 5 cm or less away from the eye. It was concluded that we do not necessarily have to use goggles to cover the entire visual field but can use a normal pair of glasses made of colored filters for young subjects to study the color perception of the elderly with understanding that the study is only for the color perception experienced while wearing the glasses.     

Magnetic moments of hindered rotators by off‐center impurity ions

Off‐center impurity ions in solids often perform rotations around their regular lattice sites. Unlike quasifree rotors with rotational line spectra subject to textbook attention in quantum mechanics, the off‐center species are hindered rotors with spectra quantized in rotational bands. These bands occur because of tunneling through barriers arising along the orbital path. For an off‐center ion rotating along a planar orbit, such as the Li⁺ impurity nearest‐neighboring an F center in alkali halide, the hindered rotation will give rise to specific magnetic moments that couple to and quantize external magnetic fields normal to the orbital plane. We present a simple theory and estimates of Li⁺ magnetic dipoles and rotational bands to find conditions for an experimental verification. © 2002 Wiley Periodicals, Inc. Int J Quantum Chem, 2002     

LiF晶体中F3^＋—F2混合色心激光器

本文报道了室温下LiF晶体中F_3~+-F_2混合色心激光器.利用一块晶体和单一泵光,输出激光波长范围从510～580nm、640～710nm.总带宽140nm.     

A Thermal And Structural Study on Lanthanum Hexacyanocobaltate(III) Pentahydrate. Part II

The thermal dehydration of La[Co(CN)₆]⋅5H₂O proceeded through at least three stages from the temperature range of30~230°C, and an abrupt mass loss occurred around 350°C and the perovskite type oxide,LaCoO₃ was obtained at 1000°C. After dehydration, the color of the anhydride changed from white to pale blue around 230°C and furthermore, the color changed to blue around 290°C. These color changes were discussed on the basis of the changes of coordination structures around Co ions. In La[Co(CN)₆]⋅5H₂O, Co³⁺ ions lie at the center of the O_h crystal field consisted of six CN^– ions. However, in the pale blue specimen, Co³⁺ ions were situated in the center of D_4h crystal field which was distorted the O_h one by lengthening of the trans CN^– ions along z-axis. In the blue specimen, Co³⁺ ions were reduced to Co²⁺ ions which were situated in the T_d crystal field formed by four CN^–ions as [Co(CN)₄]^2–. This revised version was published online in July 2006 with corrections to the Cover Date.